1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
|
# bn.py - functions for handling Canadian Business Numbers (BNs)
#
# Copyright (C) 2017 Arthur de Jong
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA
"""BN (Canadian Business Number).
A Business Number (BN) is a 9-digit identification number for businesses
issued by the Canada Revenue Agency for tax purposes. The 9-digit number can
be followed by two letters (program identifier) and 4 digits (reference
number) to form a program account (or BN15).
More information:
* https://www.canada.ca/en/services/taxes/business-number.html
* https://www.ic.gc.ca/app/scr/cc/CorporationsCanada/fdrlCrpSrch.html?locale=en_CA/
>>> validate('12302 6635')
'123026635'
>>> validate('12302 6635 RC 0001')
'123026635RC0001'
>>> validate('123456783')
Traceback (most recent call last):
...
InvalidChecksum: ...
>>> validate('12345678Z')
Traceback (most recent call last):
...
InvalidFormat: ...
"""
from stdnum import luhn
from stdnum.exceptions import *
from stdnum.util import clean, isdigits
def compact(number):
"""Convert the number to the minimal representation. This strips the
number of any valid separators and removes surrounding whitespace."""
return clean(number, '- ').strip()
def validate(number):
"""Check if the number is a valid BN or BN15. This checks the length,
formatting and check digit."""
number = compact(number)
if len(number) not in (9, 15):
raise InvalidLength()
if not isdigits(number[:9]):
raise InvalidFormat()
luhn.validate(number[:9])
if len(number) == 15:
if number[9:11] not in ('RC', 'RM', 'RP', 'RT'):
raise InvalidComponent()
if not isdigits(number[11:]):
raise InvalidFormat()
return number
def is_valid(number):
"""Check if the number is a valid BN or BN15."""
try:
return bool(validate(number))
except ValidationError:
return False
|